Cancers are shown as the major causes of death. Earlier detecting of cancer, inhibiting the development and spread of cancer cells, and even researching a method for preventing cancer cells are major issues focused by researchers and the public.
Colorectal cancer (CRC) has been the third common cancer among all cancers. Every year, there are a million new cases and 500,000 people death due to the colorectal cancer. Researches reveal earlier detection and diagnosis will help to decrease the mortality and morbidity of colorectal cancer.
Screening methods currently available for detecting the colorectal cancer include digital rectal examination, fecal occult blood test (FOBT), sigmoidoscopy, and colonoscopy. Although above-mentioned methods have improved the detection efficiency of the colorectal cancer, however, their diagnostic value as a general screening tool is limited because of poor sensitivity and a high false positive rate (FOBT), costs, risks, and inconvenience (colonoscopy). To overcome these problems, the development of novel biomarkers that can allow for the early detection of CRC is crucial.
The advancement of molecular biology, proteomic and preventive medicine provide more useful information or tools to increase the proceeding of develop a novel detection or therapy for colorectal cancer. A biomarker revealing over-expression in tumor tissues (i.e. a tumor tissue or a tissue biopsy) by using one of above-mentioned methods might not release to the circulation of the blood, show a large amount of expression in the blood, or has a long half-life to be detected. A carcinoembryonic antigen (CEA), a clinically established serological marker, is a marker currently widely used in colorectal cancer detection but is always suggested to be used in estimating the prognosis of CRC patients due to the limited sensitivity and specificity.
Accordingly, using different biotechnological methods to search and develop a biomarker to earlier diagnosis the colorectal cancer and to improve the therapeutic efficiency is very important